A sustained-release gel compression strength testing device

Abstract

The utility model provides a sustained-release gel compression strength detection device to solve the problem of difficult temperature control during the compression strength test of the sustained-release gel, comprising: a base, a pressure-bearing seat is arranged on the top, a groove is arranged on the pressure-bearing seat, a medium flow channel is arranged inside the pressure-bearing seat, one end is connected with the groove, and the other end extends to the outside and is connected with a temperature regulating device; a fixed bracket is fixedly connected to the top of the base; a compression component is composed of a connecting rod, a pressure gauge, and a pressure block, and the pressure gauge is fixedly connected between the lower end of the connecting rod and the upper end of the pressure block; a driving component is connected to the fixed bracket; a shield is composed of a main shell and a cover plate connected to the upper part of the main shell by sliding up and down, and the cover plate is fixedly connected to the lower part of the connecting rod and is located above the pressure gauge. The device can realize stable control of the temperature of the sample to be tested, and improve the accuracy of the compression strength test result.

Description

Technical Field

[0001] The utility model relates to the technical field of medical devices, in particular to a sustained-release gel compression strength detection device. Background Art

[0002] Sustained-release gel is a semisolid preparation that can control the slow release of drugs. It achieves continuous and stable release of drugs through a special gel network structure. It is usually a three-dimensional network structure formed by polymer materials, which can encapsulate and control the release rate of drugs.

[0003] After the sustained-release gel is produced, its mechanical strength and structural stability need to be evaluated, among which compression strength is an important parameter. By testing the compression strength of the product, it is ensured that it will not break or deform during use, the structural stability of the drug delivery system is guaranteed, and the patient comfort is improved. However, changes in temperature will cause changes in the hydrogel network structure, resulting in changes in water content, cross-linking density, etc., thereby affecting the mechanical properties of the hydrogel and directly affecting the compression strength test results.

[0004] Existing sustained-release gel measuring devices generally use universal testing machines or open compression devices, which cannot guarantee the temperature of the sample to be tested before and during the measurement. Even if the temperature of the sample to be tested is controlled, it is often taken out for testing after being kept warm in a constant temperature box or other equipment. During operation, if the temperature difference between the external environment and the required temperature of the sample to be tested is large, heat exchange will occur, and it is impossible to ensure that the sample temperature meets the test requirements and the consistency of the test temperature between different samples, thereby affecting the test results. Utility Model Content

[0005] The utility model provides a sustained-release gel compression strength detection device to solve the problem of difficult temperature control during the compression strength test of the sustained-release gel. In order to achieve the above purpose, the technical scheme adopted is as follows:

[0006] A sustained-release gel compression strength testing device, comprising:

[0007] The base has a pressure-bearing seat disposed on the top, a groove disposed on the pressure-bearing seat, a medium flow channel disposed inside the pressure-bearing seat, one end of the medium flow channel is connected to the groove, and the other end extends to the outside and is connected to a temperature regulating device, the temperature regulating device includes a heat exchanger and an air pump, and the air inlet and air outlet of the heat exchanger are respectively connected to the air outlet of the air pump and the medium flow channel;

[0008] A fixed bracket, fixedly connected to the top of the base;

[0009] The compression assembly is composed of a connecting rod, a pressure gauge and a pressing block, wherein the pressure gauge is fixedly connected between the lower end of the connecting rod and the upper end of the pressing block, and the size of the pressing block is smaller than the groove;

[0010] A driving assembly, connected to the fixed bracket, used to drive the connecting rod to move up and down in the vertical direction;

[0011] The protective cover is composed of a main shell and a cover plate connected to the upper part of the main shell by sliding up and down. The outer diameter of the main shell is not larger than the outer diameter of the pressure seat and the inner diameter is not smaller than the outer diameter of the groove. The cover plate is fixedly connected to the lower part of the connecting rod and is located above the pressure gauge.

[0012] Furthermore, a pressure relief pipe is connected to the cover plate, and a pressure relief valve is arranged on the pressure relief pipe.

[0013] Furthermore, the drive assembly consists of a servo motor, a lead screw, and a lead screw nut. The servo motor is fixedly connected to a fixed bracket and the output end is transmission-connected to the lead screw. The length of the lead screw is distributed in a vertical direction and the upper and lower ends are respectively rotatably connected to the fixed bracket. The lead screw nut is threadedly connected to the lead screw and fixedly connected to the connecting rod.

[0014] Furthermore, the inner wall of the main shell is provided with sliding grooves distributed along the vertical direction, and the outer end of the cover plate is slidably connected to the sliding grooves up and down.

[0015] Furthermore, a spring is provided between the lower end of the cover plate and the sliding groove, and the length of the spring is distributed along the vertical direction.

[0016] Furthermore, a first sealing ring is provided at the lower end of the main shell.

[0017] Furthermore, a second sealing ring is provided at the outer end of the cover plate.

[0018] Furthermore, a temperature sensor is also provided at the lower end of the cover plate.

[0019] Furthermore, the medium flow channel is also connected to a liquid adding pipe, and a first switch valve and a second switch valve are respectively provided on the air outlet of the heat exchanger and the liquid adding pipe.

[0020] Furthermore, a guide groove is provided at the lower part of the connecting rod, a guide block is slidably connected up and down in the guide groove, and the guide block is fixedly connected to the pressure gauge.

[0021] The beneficial effects of the utility model are:

[0022] 1. The protective cover and the pressure bearing seat are arranged to form a closed space. The sample to be tested is placed in the closed space and its temperature is adjusted by the temperature regulating device to ensure that the sample to be tested is within a suitable temperature range before the compression strength test, avoiding the problem of temperature change of the sample to be tested during transfer or testing, thereby improving the accuracy of the test results;

[0023] 2. The shield consists of a main shell and a cover plate. The cover plate is fixedly connected to the connecting rod and can be slid up and down to the main shell. Therefore, during the insulation stage, it can ensure that the sample to be tested within a certain thickness range does not contact the pressing block. When the insulation is completed, the cover plate can be moved down with the connecting rod to perform the compression strength test of the sample to be tested, thereby completing the continuous operation of insulation and compression strength test;

[0024] 3. By arranging a pressure relief pipe and a pressure relief valve on the cover plate and coordinating with gas for heat exchange, the opening pressure of the pressure relief valve is pre-set according to the pressure requirements of the actual use environment of the sample to be tested before use. When the internal pressure is too high, the pressure is adjusted through the pressure relief valve to further improve the accuracy of the test results of the sample to be tested;

[0025] 4. Sealing rings are provided between the cover plate and the main shell, and between the lower end of the main shell and the upper end of the pressure-bearing seat to further improve the airtightness and thus improve the thermal insulation effect;

[0026] 5. Through the spring arranged between the lower part of the cover plate and the slide groove of the main shell, the connecting rod can press the main shell and the pressure-bearing seat through the cover plate and the spring, thereby improving the sealing between the main shell and the pressure-bearing seat during the heat preservation stage and further improving the heat preservation effect;

[0027] 6. The setting of the liquid adding pipe can provide the medium simulation liquid with appropriate concentration, pH value and other parameters for the sample to be tested after the insulation is completed, so as to meet the actual use environment of the sample to be tested, and further improve the application scope of the device;

[0028] 7. Through the setting of the guide block and the guide groove, the pressure gauge and the pressure block can be slid up and down and connected under the connecting rod, which can adapt to the test of samples with larger thickness. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the structure of the first embodiment of the utility model

[0030] Figure 2 for Figure 1 A partial enlarged schematic diagram

[0031] Figure 3 for Figure 1 Schematic diagram of the contact state between the middle pressure block and the sample

[0032] Figure 4 This is a schematic diagram of the second embodiment of the utility model

[0033] Figure 5 for Figure 4 A partial enlarged diagram of point B in the middle

[0034] in:

[0035] 1-base, 2-fixed bracket, 3-servo motor, 4-screw, 5-screw nut, 6-connecting rod, 601-guide groove, 7-pressure gauge, 8-pressure block, 9-pressure seat, 901-groove, 902-through hole, 903-medium flow channel, 10-main shell, 1001-slide groove, 11-cover plate, 12-connecting pipe, 13-first switch valve, 14-heat exchanger, 15-air pump, 16-first sealing ring, 17-second sealing ring, 18-temperature sensor, 19-spring, 20-liquid adding pipe, 21-second switch valve, 22-pressure relief pipe, 23-pressure relief valve, 24-sample to be tested, 25-guide block. DETAILED DESCRIPTION

[0036] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0037] In the description of the utility model, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the viewing direction or position relationship, and are only for the convenience of describing the utility model, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model.

[0038] First embodiment

[0039] like Figure 1-Figure 3 A sustained-release gel compression strength testing device shown includes a base 1, a fixed bracket 2, a driving assembly, and a compression assembly. The fixed bracket 2 is fixedly connected to the top of the base 1, and the driving assembly is arranged on the fixed bracket 2 to drive the compression assembly to perform a compression strength test on the sample 24 to be tested.

[0040] Specifically, the driving assembly includes a servo motor 3, a lead screw 4, and a lead screw nut 5. The servo motor 3 is fixedly connected to the top of the fixed bracket 2. The length of the lead screw 4 is distributed in the vertical direction. The upper and lower ends of the lead screw 4 are rotatably connected to the upper and lower ends of the fixed bracket 2 through bearings, and the upper end of the lead screw 4 is transmission-connected to the output end of the servo motor 3. The lead screw 4 is driven to rotate by the servo motor 3, thereby driving the lead screw nut 5 to move up and down.

[0041] like Figure 1 and Figure 2As shown, the compression assembly includes a connecting rod 6, a pressure gauge 7 and a pressure block 8. The connecting rod 6 is an L-shaped rod structure composed of a horizontal rod and a longitudinal rod. One end of the horizontal rod is fixedly connected to the screw nut 5, and the longitudinal rod is distributed in the vertical direction and the lower end is fixedly connected to the pressure gauge 7. The pressure block 8 is fixedly connected below the pressure gauge 7.

[0042] A pressure bearing seat 9 is also provided above the base 1, and the pressure bearing seat 9 is located directly below the compression assembly. Specifically, Figure 1-Figure 3 As shown, a groove 901 is provided on the upper end surface of the pressure seat 9, and the size of the groove 901 is larger than that of the pressure block 8. A plurality of groups of through holes 902 are provided on the outer edge of the groove 901. A medium flow channel 903 is provided inside the pressure seat 9, and the plurality of groups of through holes 902 are all connected to the medium flow channel 903. The medium flow channel 903 extends to the outside and is connected to the temperature regulating device through the connecting pipe 12. The temperature regulating device includes a heat exchanger 14 and an air pump 15. The air inlet and the air outlet of the heat exchanger 14 are respectively connected to the air outlet of the air pump 15 and the connecting pipe 12.

[0043] The lower end of the connecting rod 6 is also connected to a protective cover, which is composed of a main shell 10 and a cover plate 11. The upper and lower ends of the main shell 10 are opened, and the outer diameter is the same as that of the pressure seat 9 and is greater than or equal to the diameter of the groove 901. A slide groove 1001 is arranged on the inner wall of the main shell 10, and the length of the slide groove 1001 is distributed in the vertical direction. The cover plate 11 is fixedly connected to the connecting rod 6 and the outer end can be slid up and down in the slide groove 1001. The servo motor 3 can drive the screw nut 5 and the connecting rod 6 to move up and down. When moving downward to compress the sample 24 to be tested, when the main shell 10 descends to the lower end and contacts the upper end of the pressure seat 9, the connecting rod 6 continues to move downward to drive the cover plate 11 to move downward, thereby sealing the pressure seat 9 through the protective cover. In order to facilitate observation, a transparent material can be selected for the cover plate 11 and the main shell 10.

[0044] In order to improve the sealing effect of the overall structure, a first sealing ring 16 is arranged at the lower end of the main shell 10, and a second sealing ring 17 is arranged at the outer end of the cover plate 11; moreover, a pressure relief pipe 22 is also connected to the cover plate 11, the lower end of the pressure relief pipe 22 passes through the cover plate 11, and the upper end is located above the cover plate 11 and is connected to a pressure relief valve 23. When the connecting rod 6 drives the shield and the pressure-bearing seat 9 to form a closed space and then continues to drive the cover plate 11 to move downward to compress the sample 24 to be tested, the pressure relief pipe 22 and the pressure relief valve 23 are arranged to avoid excessive internal pressure, and the opening pressure of the pressure relief valve 23 is set according to the actual use environment of the sample 24 to be tested (such as in vivo or in vitro), so that the test space where the sample 24 to be tested is located can be in a suitable pressure environment.

[0045] A spring 19 is also arranged between the lower part of the outer end of the cover 11 and the slide groove 1001. Due to the arrangement of the spring 19, when the main shell 10 contacts the pressure seat 9, the connecting rod 6 continues to move downward a certain distance, which can cause the cover 11 to compress the spring 19 downward, thereby applying downward pressure to the main shell 10, thereby improving the sealing effect between the main shell 10 and the pressure seat 9, facilitating subsequent insulation operations. Moreover, it should be noted that when insulation is performed, when the first sealing ring 16 at the lower end of the main shell 10 contacts the upper end of the pressure seat 9, it can continue to move downward a certain distance, but it is necessary to ensure that the pressure block 8 does not contact the sample 24 to be tested.

[0046] In addition, a liquid adding tube 20 is also connected to the connecting tube 12, and a second switch valve 21 is arranged on the liquid adding tube 20. A first switch valve 13 is arranged at one end of the connecting tube 12 close to the heat exchanger 14. By setting the liquid adding tube 20, a medium liquid matching the use environment of the sample to be tested 24, such as an environmental simulation liquid with a corresponding temperature, concentration and pH value, can be added to the groove 901 to ensure that it matches the physiological conditions of the human body or the use environment conditions.

[0047] When the device is used to test the compressive strength of the sample 24 to be tested, the working principle is as follows:

[0048] First, select a sample 24 of appropriate size and thickness and place it in the groove 901. The servo motor 3 drives the lead screw nut 5 and the connecting rod 6 to move downward until the lower end of the main shell 10 of the shield contacts the upper end of the pressure seat 9. When appropriate, it can continue to move downward to a certain height to ensure that the lower end of the main shell 10 is in close contact with the upper end surface of the pressure seat 9 to improve the sealing effect and avoid the main shell 10 from moving up during insulation. At this time, it should be ensured that the pressure block 8 does not contact the sample 24 to be tested. Then the air pump 15 and the heat exchanger 14 work, and open the first switch valve 13 to transport gas into the groove 901 through the connecting pipe 12 and the medium flow channel 903. The gas after heat exchange and the opening pressure of the pressure relief valve 23 should meet the use environment of the sample 24 to be tested. The internal temperature can be monitored in real time by the temperature sensor 18. After the sample 24 to be tested is kept warm for a certain period of time, the servo motor 3 continues to drive the connecting rod 6 and the pressure block 8 to move downward to perform a compression strength test on the sample 24 to be tested.

[0049] Of course, if the use environment of the sample 24 to be tested requires liquid or has requirements on the concentration and pH value of the medium, after the insulation is completed, the first switch valve 13 can be closed first, and then the second switch valve 21 can be opened to add the medium liquid that meets the requirements into the groove 901 through the liquid adding pipe 20.

[0050] It should be noted that, in this embodiment, when the first sealing ring 16 at the lower end of the main shell 10 is in close contact with the upper end of the pressure seat 9, there is no contact between the pressure block 8 and the sample to be tested 24, and the height to which the cover plate 11 can slide down along the slide groove 1001 is greater than the gap between the pressure block 8 and the sample to be tested 24.

[0051] In addition, in order to facilitate the cleaning of the pressure-bearing seat 9, the pressure-bearing seat 9 and the base 1 can be set to be detachably connected, such as by setting corresponding mounting holes and fastening them together through bolts. This structure belongs to the conventional technical means in this field, so it will not be described in detail in this embodiment.

[0052] Second embodiment

[0053] This embodiment provides a sustained-release gel compression strength detection device, the overall structure of which is the same as that of the first embodiment, except for the arrangement of the compression component.

[0054] Specifically, Figure 4 and Figure 5 As shown, the compression assembly includes a connecting rod 6, a guide block 25, a pressure gauge 7 and a pressure block 8. The lower end of the connecting rod 6 is provided with a guide groove 601. The guide block 25 can be slidably connected in the guide groove 601 up and down, and the lower end of the guide block 25 is fixedly connected to the pressure gauge 7. The pressure block 8 is connected below the pressure gauge 7. In the state where the lower end of the main shell 10 is in contact with the upper end of the pressure-bearing seat 9, if the thickness of the sample 24 to be tested is greater than the gap between the pressure block 8 and the groove 901, the pressure block 8 will drive the guide block 25 to move up along the guide groove 601 until it moves to the upper end surface of the guide groove 601. If there is still a gap between the sample 24 to be tested and the pressure block 8, after the insulation is completed, the connecting rod 6 drives the cover plate 11 to move down until the pressure block 8 contacts the sample 24 to be tested first, and then the pressure block 8 moves up to the upper end of the guide groove 601 through the guide block 25. Then, the pressure block 8 performs a compression strength test on the sample 24 to be tested under the continued drive of the connecting rod 6.

[0055] It should be noted that a connection member is provided between the guide block 25 and the connecting rod 6. Figure 5 The limiting structure of the limiting boss and the limiting groove shown is used to prevent the guide block 25 from sliding down out of the guide groove 601. This structure belongs to a conventional mechanical limiting structure, so it will not be described in detail in this embodiment.

[0056] The pressure gauge 7 and the pressure block 8 are connected by sliding up and down between the guide block 25 and the connecting rod 6. The arrangement of this structure can adapt to the compression strength test of the sample 24 to be tested with a larger thickness.

[0057] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements can be made without departing from the principle of the present invention, and these improvements should also be regarded as the protection scope of the present invention.

Claims

1. A sustained-release gel compression strength testing device, characterized in that: include: The base has a pressure-bearing seat disposed on the top, a groove disposed on the pressure-bearing seat, a medium flow channel disposed inside the pressure-bearing seat, one end of the medium flow channel is connected to the groove, and the other end extends to the outside and is connected to a temperature regulating device, the temperature regulating device includes a heat exchanger and an air pump, and the air inlet and air outlet of the heat exchanger are respectively connected to the air outlet of the air pump and the medium flow channel; A fixed bracket, fixedly connected to the top of the base; The compression assembly is composed of a connecting rod, a pressure gauge and a pressing block, wherein the pressure gauge is fixedly connected between the lower end of the connecting rod and the upper end of the pressing block, and the size of the pressing block is smaller than the groove; A driving assembly, connected to the fixed bracket, used to drive the connecting rod to move up and down in the vertical direction; The protective cover is composed of a main shell and a cover plate connected to the upper part of the main shell by sliding up and down. The outer diameter of the main shell is not larger than the outer diameter of the pressure seat and the inner diameter is not smaller than the outer diameter of the groove. The cover plate is fixedly connected to the lower part of the connecting rod and is located above the pressure gauge.

2. The sustained-release gel compression strength testing device according to claim 1, characterized in that: The cover plate is connected with a pressure relief pipe, and the pressure relief pipe is provided with a pressure relief valve.

3. The sustained-release gel compression strength testing device according to claim 1, characterized in that: The driving assembly consists of a servo motor, a lead screw, and a lead screw nut. The servo motor is fixedly connected to a fixed bracket and the output end is transmission-connected to the lead screw. The length of the lead screw is distributed in the vertical direction and the upper and lower ends are rotationally connected to the fixed bracket respectively. The lead screw nut is threadedly connected to the lead screw and fixedly connected to the connecting rod.

4. The sustained-release gel compression strength testing device according to claim 1, characterized in that: The inner wall of the main shell is provided with sliding grooves distributed along the vertical direction, and the outer end of the cover plate is slidably connected in the sliding grooves up and down.

5. The sustained-release gel compression strength testing device according to claim 4, characterized in that: A spring is arranged between the lower end of the cover plate and the sliding groove, and the length of the spring is distributed along the vertical direction.

6. The sustained-release gel compression strength testing device according to claim 1, characterized in that: A first sealing ring is arranged at the lower end of the main housing.

7. The sustained-release gel compression strength testing device according to claim 1, characterized in that: A second sealing ring is arranged at the outer end of the cover plate.

8. The sustained-release gel compression strength testing device according to claim 1, characterized in that: A temperature sensor is also arranged at the lower end of the cover plate.

9. The sustained-release gel compression strength testing device according to claim 1, characterized in that: The medium flow channel is also connected to a liquid adding pipe, and a first switch valve and a second switch valve are respectively arranged on the air outlet of the heat exchanger and the liquid adding pipe.

10. The sustained-release gel compression strength testing device according to claim 1, characterized in that: A guide groove is arranged at the lower part of the connecting rod, a guide block is slidably connected in the guide groove, and the guide block is fixedly connected to the pressure gauge.

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